Update from N3 and N4:
- Catherine: out-scaling RMS strategies
- An: framework for targeting and priority setting
- Solomon: SWAT/WEAP
- Teklu: CWP
- Kinde: Ecosaut
We agreed to:
- model three “alternative options”: (i) campaign, (ii) most likely SLM strategy – maximum implementation, (iii) most likely SLM strategy – partially adopted
- include the following impact indicators in the assessment: Reduced sediment (at nodes), Reduced nutrient loss, Reduced gully density, Reduced surface run-off, Reduced erosion in sub catchments, Groundwater recharge, Increased dry season soil moisture, Increased base flow, Reduced evaporation, Increased transpiration, Increased biomass, Increased livestock productivity, livelihood diversification, Increased income, something on ecosystem services, Increased ground cover, Change in labour (gender disaggregated?)
Action plan:
- Refine suitability criteria: Catherine and Teklu – Tuesday 29th May - 9AM
- Define most likely strategy: Abisalom, Yenenesh, Catherine – setting up the modeling on Monday; to be finalised in about 2 weeks
- Quantify strategies: Solomon, Charlotte + all N4 modelers – mid June
- Send out impact table: Charlotte – next week
- Actual impact assessment: September
- Synthesis, write-up: October
- Feed back to partners, IPs, etc: to be discussed with N2 and N5
Impact Indicators:
Indicator:
How to model / assess?...
Reduced sediment (at nodes)
Don: In measuring sediment, it is critical to look at the timing. A few heavy rainfall events will have a disproportionate impact on erosion, sedimentation and run-off. Thus unless you are monitoring continuously, there is a good chance that you will miss key events.
Tammo: Moreover, sediment concentration is dependent on runoff amounts and time of the year. The only way to see if erosion is reduced might be to calibrate the model with pre bmp data and see if the model over predicts after BMP installation. In the Catskills Stedinger has done this successfully but the paper never has been published because the student became fed-up with CEE in Cornell. We have used the technique for phosphorus and stream flow successfully. I will find the paper. We used in Rao et al a simple model, but SWAT might work. The simple erosion mode that we developed might work just as well. The same is true for nutrients. Only by comparing it with a model it might be possible. We should be realistic the duration of three years is rather short
Reduced nutrient xxxx
Reduced gully density
Reduced surface run-off
Reduced erosion in sub catchments
Groundwater recharge
Increased dry season soil moisture
Don: Dry season soil moisture also needs to monitored closely. A key positive change would be a reduced rate at which soil dries out. Thus one might need to measure soil moisture changes every day or every week or so following the cessation of the rainy period.
Tammo: In addition one need to do this at various locations in the watershed. One can fit the moisture content data against the Thornthwaite Mather procedure and by doing so a fitted “plant available water” is obtained for before and after the BMP implementation. The dry out period likely gives most information
Increased base flow
Reduced evaporation
Increased transpiration
Don:Increased transpiration will only be “good” if transpired water is passing through useful plants. Weeds and unsuitable tree species (e.g., some Eucalyptus species in drylands) may enhance transpiration but not help improve benefits or ecosystem health.
Tammo: It is extremely difficult to separate transpiration from evaporation. One might be able to do something with the red and infra-red bands from satellite information. I am not familiar with it but there are people at IWMI who are very good in it likely
Increased biomass?
Don:What is intended here? An overall increase of biomass may be useful but not always. The Biomass needs to be composed of plant species that are useful to nature or livelihoods. Do you mean standing biomass, production or productivity? Are you implying food crops bearing in mind that crop yields are not the same as biomass? Underground biomass is very important but usually not measured.
Tammo: May be we need to look at the amount of “effective” biomass produced per unit of water evaporated or applied. Effective is meant as Yield for grain cops and teff or amount of oil produced per crop. Again we need to separate the variability in climate from that what is caused by BMP’s
Increased livestock productivity
Don: Do you mean production or productivity? If you have this for livestock, why not for crops? In ecosystems, there is usually a trade-off between maximizing production and maximizing productivity. Do you mean livestock water productivity?
Tammo: livestock water productivity is likely the most useful
livelihood diversification
Don: Several aspects of this could be important. I know that in the Ginchi area (near Jeldu), we found that farmers’ intake of calories was inversely correlated with the degree of land degradation. Water borne diseases also are highly dependent on land and animal management as well as on the use of latrines and management of drinking water. Malaria transmission (a leading cause of mortality in Ethiopia) has been shown to be correlated with many factors including proximity to maize production.
Increased income
something on ecosystem services
Don:Some of this will be captured in the hydrological indicators that you have listed. I would also suggest that vegetative cover contributes and plant and animal biodiversity are important. Although hard to measure, there is great value in tracking soil biodiversity. In degraded land, soil biodiversity suffers and this interferes with ecosystem functioning. It might be useful to consider the level and trends in the Carbon pool and the rate at which Carbon is being sequestered or lost. We might also want to consider ecosystem disservices. For example for many farmers, wildlife and biodiversity pose threats of disease, health, and safety but for many stakeholders they can be positive assets, and so we need to evaluate services in the context of diverse stakeholders’ views.
Tammo: This is indeed a catchall for many things
Increased ground cover
Don:I presume this means plant biomass, but it could also mean litter or crop residues. These will be seasonal and thus timing is important.
Tammo: increase ground cover might be important for erosion control, but can negatively affect the soil moisture status in areas where rainfall is barely enough
Change in labour (gender disaggregated?)
Additional comments from Don/Tammo:
Depending on the scale of assessment and the historical context, wetlands are very important. Their extent and biodiversity can be assessed. Can they be introduced to the landscape? Do they exist? Are they increasing or decreasing. CPWF and other research showed how changing upslope hydrology could enhance or reduce wetland extent downslope. But wetlands can also be hotspots for animal disease transmission
Crop residue management: This might be a useful indicator (or set of them). Crop residues are needed to feed animals, are used for housing, and are needed to replenish soil fertility. They can also be a direct source of fuel or an indirect source if fed to animals and the manure is used as a fuel. From an ecosystem standpoint, it would be really interesting and I think productive to assess crop residue use and options for replenishing soil fertility. Tammo: In an experiment by McHugh near Woldya, ground cover harbored pests that destroyed the crops. I agree with Don, more is better and it needs to be taken off the field. If used for fertility is should be composted, burned or used for bio char.
23rd May 2012
Addis Abeba
Participants:
Yenenesh, Teklu, Kinde, Jens, Catherine, Lisa, Solomon, Abisalom, Michael, Charlotte, An, Simon, Beth
Update from N3 and N4:
- Catherine: out-scaling RMS strategies
- An: framework for targeting and priority setting
- Solomon: SWAT/WEAP
- Teklu: CWP
- Kinde: Ecosaut
We agreed to:
- model three “alternative options”: (i) campaign, (ii) most likely SLM strategy – maximum implementation, (iii) most likely SLM strategy – partially adopted
- include the following impact indicators in the assessment: Reduced sediment (at nodes), Reduced nutrient loss, Reduced gully density, Reduced surface run-off, Reduced erosion in sub catchments, Groundwater recharge, Increased dry season soil moisture, Increased base flow, Reduced evaporation, Increased transpiration, Increased biomass, Increased livestock productivity, livelihood diversification, Increased income, something on ecosystem services, Increased ground cover, Change in labour (gender disaggregated?)
Action plan:
- Refine suitability criteria: Catherine and Teklu – Tuesday 29th May - 9AM
- Define most likely strategy: Abisalom, Yenenesh, Catherine – setting up the modeling on Monday; to be finalised in about 2 weeks
- Quantify strategies: Solomon, Charlotte + all N4 modelers – mid June
- Send out impact table: Charlotte – next week
- Actual impact assessment: September
- Synthesis, write-up: October
- Feed back to partners, IPs, etc: to be discussed with N2 and N5
Impact Indicators:
Tammo: Moreover, sediment concentration is dependent on runoff amounts and time of the year. The only way to see if erosion is reduced might be to calibrate the model with pre bmp data and see if the model over predicts after BMP installation. In the Catskills Stedinger has done this successfully but the paper never has been published because the student became fed-up with CEE in Cornell. We have used the technique for phosphorus and stream flow successfully. I will find the paper. We used in Rao et al a simple model, but SWAT might work. The simple erosion mode that we developed might work just as well.
The same is true for nutrients. Only by comparing it with a model it might be possible. We should be realistic the duration of three years is rather short
Tammo: In addition one need to do this at various locations in the watershed. One can fit the moisture content data against the Thornthwaite Mather procedure and by doing so a fitted “plant available water” is obtained for before and after the BMP implementation. The dry out period likely gives most information
Tammo:
It is extremely difficult to separate transpiration from evaporation. One might be able to do something with the red and infra-red bands from satellite information. I am not familiar with it but there are people at IWMI who are very good in it likely
Tammo: May be we need to look at the amount of “effective” biomass produced per unit of water evaporated or applied. Effective is meant as Yield for grain cops and teff or amount of oil produced per crop. Again we need to separate the variability in climate from that what is caused by BMP’s
Tammo: livestock water productivity is likely the most useful
Tammo: This is indeed a catchall for many things
Tammo:
increase ground cover might be important for erosion control, but can negatively affect the soil moisture status in areas where rainfall is barely enough
Additional comments from Don/Tammo:
N3-N4meeting.ppt
framework_120523.pptx
Biophysical_Impacts_N4_N3_52312.ppt
Bio-economic model for assessing and anticipating economic values.ppt
Anticipating Impacts AWM Interventions.pptx